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Subject[PATCH 2/3 RESEND] x86, acpi: On S3 failure, just fall through
Date
Th "jmp" deleted by this patch in fact compiles to "jmp to next insn",
since ".p2align 4,,7" happens to not do any alignment -
aligning to 2^4 would require more than 7 bytes of padding:

000000b0 <do_suspend_lowlevel>:
b0: e8 fc ff ff ff call <save_processor_state>
b5: e8 8d ff ff ff call 47 <save_registers>
ba: 6a 03 push $0x3
bc: e8 fc ff ff ff call <x86_acpi_enter_sleep_state>
c1: 83 c4 04 add $0x4,%esp
c4: eb 00 jmp c6 <ret_point> <============ THIS
000000c6 <ret_point>:
c6: e8 c4 ff ff ff call 8f <restore_registers>

Run-tested.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Pavel Machek <pavel@ucw.cz>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Borislav Petkov <bp@alien8.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
---
arch/x86/kernel/acpi/wakeup_32.S | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
index eef2bd3..5fec9b0 100644
--- a/arch/x86/kernel/acpi/wakeup_32.S
+++ b/arch/x86/kernel/acpi/wakeup_32.S
@@ -68,11 +68,8 @@ ENTRY(do_suspend_lowlevel)
pushl $3
call x86_acpi_enter_sleep_state
addl $4, %esp
+# If S3 fails, we simply fall through to S3 wakeup code:

-# In case of S3 failure, we'll emerge here. Jump
-# to ret_point to recover
- jmp ret_point
- .p2align 4,,7
ret_point:
call restore_registers
call restore_processor_state
--
1.8.1.4


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